A rotor for a brushless motor which can securely prevent an idle running and a scattering of a magnet while restricting a manufacturing cost as low as possible. The rotor is provided with a sintered ring magnet in which not-ground recess portions are formed in an axial direction of a inner peripheral surface in correspondence to a magnetic pole, and a portion between the recess portions is ground in an inner peripheral surface having a desired inner diameter, a rotor yoke in which convex portions each having a larger diameter than the inner diameter of the sintered ring magnet are formed in an axial direction of an outer peripheral surface in correspondence to the recess portion, and a through hole is pierced in an axial center, and which is concentrically adhered to the sintered ring magnet by fitting the recess portions and the convex portions, and a shaft inserted and fitted to the through hole of the rotor yoke.